MIDI DESIGNER
The only MIDI controller for iPad, iPhone, and Mac


Talk to other MIDI Designer users about MIDI Designer, iOS MIDI and related topics. Or share layouts, pages, and ideas.

Check out our Facebook Group.

Of course, if you want to send us an email, feel free.

☞ Open problem reports

☞ Summary of user requests

Categories

Should two CCs in one message be handled? - MIDI Designer Q&A

Should two CCs in one message be handled?

0 votes
I am sending a lot of CCs to MIDI Designer as quickly as possible (to set the visual control values to match my device's), and I'm finding that some are received in messages that are 6 bytes long, and seem to be ignored (the controls are not set).

An excerpt from the log:

Message In: Cmd=176|Ch=07|Data1=009|Data2=003 | Length=3: B6 09 03
Message In: Cmd=176|Ch=07|Data1=010|Data2=002 | Length=3: B6 0A 02
Message In: Length=6: B7 00 29 B7 01 7F
Message In: Cmd=176|Ch=08|Data1=003|Data2=001 | Length=3: B7 03 01
Message In: Cmd=176|Ch=08|Data1=005|Data2=029 | Length=3: B7 05 1D

The B7 00 29 & B7 01 7F in the 6-byte message do not appear to be received as MIDI messages.

I see this behaviour when using a MIDI over Bluetooth (low energy) interface with the midimittr app presenting a standard MIDI interface to MIDI Designer on the iPad. I don't see this problem with a hardware MIDI interface (iRig MIDI). So I'm not sure whether the problem is that midimittr is not packaging the messages correctly, or that MIDI Designer is not handling the 6-byte message with two 3-byte MIDI messages in it.

Would appreciate any comments.

Thanks.
in Defect (Confirmed, Not Fixed Yet) by gutbag (350 points)
recategorized by MIDI Designer Team (Dan)
Can you send over wifi to test? Theoretically the packets should get separated but apparently that's not happening
by MIDI Designer Team (Dan)
Not sure I can try it over WiFi - certainly not from the real device. If I can send a MIDI file from a MacBook to the iPad over WiFi, then maybe. If you think that's worth doing, any tips as to how to achieve it?

What should separate the packets? If it's a midimittr problem, I can approach the developer.
by gutbag (350 points)
It's not a mittmttr problem, it's our issue: in theory, we're supposed to bust up the packets, but we only do that for sysex since we've NEVER seen combined packets for Control Changes.

Are you running iOS 8? Then we can try with the new beta, which has Bluetooth. I can add you to the test group.
by MIDI Designer Team (Dan)
Great, thanks - that makes sense. Yes, I'm still using iOS8 and I'm happy to try a new beta.
by gutbag (350 points)
One more thing... when you say that the new beta has Bluetooth, do you mean that I won't need the intermediate midimittr app?
by gutbag (350 points)
OK, I've tried it and answered that question. Nice not to have to use another app - thanks.
by gutbag (350 points)
There are no 6-byte MIDI messages with the built-in Bluetooth implementation?
by MIDI Designer Team (Dan)
That problem is still there. I tried the same test as with the released MD + midimittr. BTW, I was able to connect to the Bluetooth device from within MD, but the status at the top RH corner still said "no connection".
by gutbag (350 points)
Ok, good info, thanks. I'll circle back in a day or two, we're fighting some fires with iOS 9 for now.
by MIDI Designer Team (Dan)
Hi there, there's a bug in our MIDI implementation where bunched messages aren't being handled. This is not going to be fixed in the next production release of MD but we'll handle it in your Beta soon. Thanks for your patience.
by MIDI Designer Team (Dan)
OK, thanks. Happy to use a beta for a while.
by gutbag (350 points)
Hi, is there any news on when there might be a version with this problem fixed?

Thanks.
by gutbag (350 points)
No news yet, please hang tight. Also: are you on the Beta team and if not, can we add you to test this fix when it comes into focus?
by MIDI Designer Team (Dan)
Yes, I get TestFlight emails about new betas, which I scour for news of this. Looking forward to having the fix.
by gutbag (350 points)
Thanks. We're still working on fixing issues present in 1.7.1 and 1.7.2... once those are done, we'll move on to this one. Looking forward to getting you working as soon as we can.
by MIDI Designer Team (Dan)
Looking into this today. Unfortunately the code that handles this is looking perfect and responds perfectly to unit testing... still investigating.
by MIDI Designer Team (Dan)
Build is being submitted to Beta now. Hopefully to you in minutes. Thanks for your patience and for tracking this down. Great find!
by MIDI Designer Team (Dan)
Hi, I've tested the beta and it looks good. I fired loads of messages at it from the same device that found the problem in the first place, checked the log and there were no missed messages. Great!

Thanks for fixing this. Being able to go wireless makes a big difference to me.
by gutbag (350 points)
Glad to hear the good news and glad to help. When we release 1.7.3, we'll mark this as fixed. Thanks!
by MIDI Designer Team (Dan)

1 Answer

0 votes
 
Best answer
Sorry about this, it's a bug. Your message is being interpreted as a 6-byte Bank Select, even though the second relevant byte (the fifth byte) is not a 0x20. Fixing it ASAP.

And thanks for the awesome find. This bug has been in MD for years.
by MIDI Designer Team (Dan)
edited by MIDI Designer Team (Dan)
Powered by Question2Answer
...